#include <stdio.h>
#include <stdlib.h>
#define CNTL_Z '\032' /* DOS文本文件中的文件结尾标记 */
#define SLEN 81
int main(void)
{ 
char file[SLEN];
char ch;
FILE *fp;
long count, last;
puts("Enter the name of the file to be processed:");
scanf("%80s", file);
if ((fp = fopen(file, "rb")) == NULL)
{ /* 只读模式 */
printf("reverse can't open %s\n", file);
exit(EXIT_FAILURE);
} 
fseek(fp, 0L, SEEK_END); /* 定位到文件末尾 */
last = ftell(fp);
for (count = 1L; count <= last; count++)
{ 
fseek(fp, -count, SEEK_END); /* 回退 */
ch = getc(fp);
if (ch != CNTL_Z && ch != '\r') /* MS-DOS 文件 */
putchar(ch);
} 
putchar('\n');
fclose(fp);
return 0;
}